Last week in class I used the Latin phrase “Simul Justus et Peccator” to explain the relationship between someone who has been justified by Christ, and yet still continues to sin. It means “at once (at the same time) justified and yet sinful (a sinner).” It describes one of those paradoxical relationships that we all know all too well.
Paul, who had written about His life in Christ and freedom from the damnation of sin (death) in Romans 6, then went on to describe the struggle he still maintained in the flesh in chapter 7. Praise God that he got to chapter 8 which tells us that there is therefore now no condemnation for all those who are in Christ (8:1).
The point is that if you have been saved, you can never be un-saved. You can never do something so unrighteous that you jeopardize your position before God – Paul explains this at the end of Romans 8:
 For those whom he foreknew he also predestined to be conformed to the image of his Son, in order that he might be the firstborn among many brothers.  And those whom he predestined he also called, and those whom he called he also justified, and those whom he justified he also glorified.
 What then shall we say to these things? If God is for us, who can be against us?  He who did not spare his own Son but gave him up for us all, how will he not also with him graciously give us all things?  Who shall bring any charge against God’s elect? It is God who justifies.  Who is to condemn? Christ Jesus is the one who died—more than that, who was raised—who is at the right hand of God, who indeed is interceding for us.  Who shall separate us from the love of Christ? Shall tribulation, or distress, or persecution, or famine, or nakedness, or danger, or sword?  As it is written, “For your sake we are being killed all the day long; we are regarded as sheep to be slaughtered.”  No, in all these things we are more than conquerors through him who loved us.  For I am sure that neither death nor life, nor angels nor rulers, nor things present nor things to come, nor powers,  nor height nor depth, nor anything else in all creation, will be able to separate us from the love of God in Christ Jesus our Lord. (Romans 8:29-39 ESV)
The whole point of this passage was to give Christians the confidence to 1. know that no matter how much they sinned they still had forgiveness and salvation and justification in Christ and that nothing could separate them from His love, and 2. that no matter how morally good they were they would never have to worry about attaining to the love and righteousness that is provided us by Christ. It is HIS righteousness that will be given you on that final day, not your own.
And this is the amazing truth behind that little Latin phrase that Luther coined and that I bring up now and again. I suggestion you memorize that phrase, and remind the Devil of it whenever he tempts you toward thinking that your own morality is something (when its not), and when you begin to fret that your sins are too great for our King to overcome, for they are not.
Once justified, always justified – now that’s something worth celebrating!
For more resources on this, check out R.C. Sproul’s blog post/video on how Luther’s discovery of the truth here.